Leesman, 26, went 4-3 with a 3.87 ERA (38 ER/88.1 IP) and 78 strikeouts over 16 starts with Charlotte this season. He began the season on the disabled list while recovering from ACL surgery in 2012.

Leesman made his major-league debut in the second game of a doubleheader on August 9 vs. Minnesota, allowing one run on four hits with eight strikeouts over 5.0 IP of a no decision. His eight strikeouts were the most by a Sox pitcher in his debut since Ravelo Manzanillo also fanned eight on September 25, 1988 vs. Seattle (Elias). Leesman was optioned back to Charlotte following that game.

The 6-foot-4, 210-pound Leesman entered the season rated by Baseball America as the No. 11 Prospect and possessing the Best Changeup in the Sox organization. Leesman, who will wear uniform No. 61, originally was selected by the White Sox in the 11th round of the 2008 First-Year Player Draft.

Anderson, 26, batted .224 (47-210) with seven home runs and 26 RBI in 64 games with Charlotte this season. The 6-foot-1, 200-pound Anderson has 25 games of major-league experience with the St. Louis Cardinals (2010 and 2012), going 12-44 (.273) with no home runs and four RBI.

Anderson, who will wear uniform No. 39, signed with the White Sox as a free agent on November 11, 2012.

With the moves, the White Sox active roster is at 27 and the 40-man roster increases to 37.